Mini-Reviews in Organic Chemistry, Volume 1, No. 1, 2004
Contents
New Applications of Indium Catalysts in
Organic Synthesis Pp.1-7
C.G.
Frost and J.P.
Hartley
[Abstract]
Role of the Medium in
High Pressure Organic Reactions. A Review Pp.9-26
G.
Jenner
[Abstract]
Combinatorial Carbohydrate Synthesis Pp.27-39
S.
Nacak Baytas and R.J. Linhardt
[Abstract]
Application of the Asymmetric Hetero Diels-Alder Reaction for Synthesising
Carbohydrate Derivatives and Glycosidase Inhibitors Pp.41-54
H.M.I.
Osborn and D. Coisson
[Abstract]
Catalytic Aldehyde Olefinations Pp.55-64
Fritz
E. Kühn and Ana M. Santos
[Abstract]
Isolable 1,2-Oxaphosphetanes:
From Curiosities to Starting Materials for the Synthesis of Olefins Pp.65-70
Fernando
Lopez-Ortiz, Jesus Garcia Lopez, Ramon Alvarez Manzaneda
and Isidro J. Perez Alvarez
[Abstract]
Preparation and Synthetic Use of Enantiopure Naphthalene Dihydrodiols Pp.77-92
G.
Sello and F. Orsini
[Abstract]
Direct and Indirect Enzymatic Methods for the
Preparation of Enantiopure Cyclic β-Amino Acids and Derivatives from β-Lactams Pp.93-102
E.
Forro and F. Fulop
[Abstract]
Biomacromolecule Surface Recognition Using Nanoparticles Pp.103-114
Catherine
M. Goodman and Vincent M. Rotello
[Abstract]
Induction of the Phase II Enzyme, Quinone Reductase, by Withanolides and Norwithanolides
from Solanaceous Species Pp.115-123
Bao-Ning Su, Jian-Qiao Gu, Young-Hwa Kang,
[Abstract]
DNA, PNA, and Their Derivatives for Precise
Genotyping of SNPs Pp.125-131
A. Kuzuya, J.-M. Zhou and M. Komiyama
Abstracts
[Back to top] New Applications of Indium Catalysts in
Organic Synthesis
C.G.
Frost and
J.P. Hartley
Indium(III) salts have received considerable
attention as Lewis acids in recent years. Their stability to co-ordinating atoms present in organic substrates makes them
excellent catalysts in substoichiometric quantities.
Stability in water allows aqueous recycling and often the use of water as a
reaction solvent. This review will focus on describing new developments in the
application of indium catalysts in synthetic organic chemistry. Transformations
that will be covered include aromatic functionalisation,
cycloaddition reactions, conjugate additions and
multi-component coupling reactions.
[Back to top] Role of the Medium in
High Pressure Organic Reactions. A Review
G.
Jenner
As a thermodynamical parameter, pressure modifies the physical
and physicochemical properties of liquids considered as media for organic
synthesis. In a first part, the review details the effect of pressure
on solubility, freezing point, and viscosity. The second paragraph examines the
pressure effects on solute-medium interactions associated with volume changes.
There are two main
pressure-sensitive interactions: electrostatic and solvophobic
interactions.
i) Considering electrostrictive
effects, the pressure rate acceleration is highest in apolar
media. This is illuminated by many examples taken from unimolecular
reactions, [4+2] and [2+2] cycloadditions, Michael
reactions, Menshutkin quaternisations,
Morita-Baylis-Hillman additions.
ii) Pressure
reduces the magnitude of solvophobic (hydrophobic, fluorophobic), interactions meaning less pressure
sensitivity of reaction rates.
In the last part,
future high pressure media are outlined i.e. supercritical fluids and ionic
liquids. However, the results reported to date do not permit to draw a clear
conclusion.
High pressure
synthetic applications are described in the light of the above emphasized
effects. The results presented in the review should allow a judicious choice of
the right medium for a rational design of a liquid phase organic synthesis
under pressure.
[Back to top] Combinatorial Carbohydrate Synthesis
S.
Nacak Baytas and R.J.
Linhardt
Combinatorial
chemistry has contributed to the preparation of biologically important
oligosaccharide and glycoconjugate libraries, with a
view of improving our understanding of the complex interaction between the
carbohydrates and their proteinbased receptors. The
combinatorial carbohydrate synthesis strategies, developed in the past decade,
provide access to small and medium size libraries. This mini review critically
examines both the solution phase and solid phase strategies that have been
reported to date.
[Back to top] Application of the Asymmetric Hetero Diels-Alder Reaction for Synthesising
Carbohydrate Derivatives and Glycosidase Inhibitors
H.M.I.
Osborn and
D. Coisson
This review
provides a discussion of recent developments in the asymmetric hetero Diels-Alder reaction (AHDAR), with particular emphasis on
the synthesis of carbohydrates, their derivatives, and inhibitors of
carbohydrate processing enzymes.
[Back to top] Catalytic Aldehyde Olefinations
Fritz
E. Kühn and Ana M. Santos
Several efficient
catalytic aldehyde olefination
reactions reported, since the late 1980s, are described. This paper deals with
the results obtained with several metals. The reaction conditions, selectivities and the yields obtained are presented.
Furthermore, the mechanisms suggested by the different authors are discussed in
some detail.
[Back to top] Isolable 1,2-Oxaphosphetanes:
From Curiosities to Starting Materials for the Synthesis of Olefins
Fernando
Lopez-Ortiz, Jesus Garcia Lopez, Ramon Alvarez Manzaneda
and Isidro J. Perez Alvarez
1,2-Oxaphosphetanes are well established intermediate species
in the Wittig reaction. Initially, isolable 1,2-oxaphosphetanes represented a source of structural
information aimed at supporting mechanistic studies. The evolution of the
subject allows the envisaging of stable 1,2-oxaphosphetanes
as precursors for the stereoselective formation of
olefins.
[Back to top] Preparation and Synthetic Use of Enantiopure Naphthalene Dihydrodiols
G.
Sello and F. Orsini
Asymmetric diols can be used in organic synthesis as chiral synthons or auxiliaries.
These two uses show different scopes. In the first case the compound
substructure must be present in the final product and, consequently, the
possibilities are limited by the number of the possible targets. In the second
case the number of variables is greater and the combinations are virtually
infinite. In this respect, the use of enantiopure diols has found large coverage, also favored by the
availability of enzymatically prepared substrates. In
this review we will focus on the use of a special subclass of diols, those derived from naphthalene precursors. An
account of both uses will be presented, taking special care of the potential
future developments. In addition, a brief account on the preparation
methodology of enantiopure 1,2-dihydro-1,2-
dihydroxy naphthalenes will
be presented.
[Back to top] Direct and Indirect Enzymatic Methods for the
Preparation of Enantiopure Cyclic β-Amino Acids and Derivatives from β-Lactams
E.
Forro and F. Fulop
Direct enzymatic
methods for the preparation of enantiopure cyclic
β-amino acids
(e.g. cispentacin) and β-lactams
through the enzyme-catalyzed enantioselective ring opening of β-lactams
in water and organic solvents are reviewed. Indirect methods through the lipase-catalyzed
asymmetric acylation of N-hydroxymethylated β-lactams
or the lipase-catalyzed hydrolysis of the corresponding ester derivatives,
followed by ring opening, are also surveyed.
[Back to top] Biomacromolecule Surface Recognition Using Nanoparticles
Catherine
M. Goodman and Vincent M. Rotello
Monolayer-protected
nanoparticles represent a new class of receptors,
capable of high affinity, multivalent binding with biomolecules.
Networks of self-optimizing bioactive substituents
can be introduced via facile place-exchange of functionalized thiols, approximating the diversified topology of
biological surfaces. Extension of these particles to model systems and in
catalysis is described.
[Back to top] Induction of the Phase II Enzyme, Quinone Reductase, by Withanolides and Norwithanolides from Solanaceous
Species
Bao-Ning Su, Jian-Qiao
Gu, Young-Hwa Kang,
The induction of
the phase II drug-metabolizing enzyme, NAD(P)H:quinone
reductase (QR), using Hepa
1c1c7 hepatoma cells, is currently used as a key
member of a panel of in vitro bioassays in our program directed towards the
discovery of new plantderived cancer chemopreventive agents. Among a group of natural products,
which have been studied as QR inducers are the withanolides,
which constitutes about 400 C28 ergostane-type
steroids found mainly in approximately 10 genera of the plant family Solanaceae. New withanolides have
been isolated and characterized in our recent work on Physalis
philadelphica (tomatillo),
which is used as a vegetable and condiment in Mexican and Central American
cuisine. A further study on Deprea subtriflora has led to the discovery of a new class of C-18
norwithanolides with only 27 carbons in their
skeleton. Preliminary structure-activity relationships have been determined for
the in vitro induction of QR by members of the withanolide
and norwithanolide classes.
[Back to top] DNA, PNA, and Their Derivatives for Precise Genotyping of SNPs
A.
Kuzuya, J.-M. Zhou and M. Komiyama
Two new approaches
for SNP genotyping are described. The one is based on tandem site-selective RNA
scission and the genotype is determined by MALDI-TOF/MS analyses of clipped
short RNA. The other is visual SNP genotyping with combinations of peptide
nucleic acid (PNA) and single-stranded DNA specific nucleases.